A vehicle door has a door trim for covering a door panel. The vehicle door trim includes, depending on a structure thereof, a wide and flat door trim attached to a door panel and a molded door trim having an arm rest or the like molded as one unit with the door trim. The door trim is used only to provide an aesthetic effect for a vehicle interior but also to provide sound insulation, sound absorption, protection of occupants at the time of crash, etc.
The vehicle door further includes a door inner belt having at least one contact rib formed thereon, which is in contact with door glass, supports the door glass from an inner side, and guides up/down movement of the door glass.
In addition, different frame members are installed on the vehicle door depending on the formation of an inner space of the door. A frame door has a relatively large width, and a slim door has less frame members to further secure the inner space.
FIG. 1 illustrates a cross-sectional view of a door frame according to the related art.
Referring to FIG. 1, a door frame of the related art has four structures including an outer panel, an outer rail, an inner panel, and an inner rail which are welded together to secure an inner space of a door.
A slim door has been used from which the outer rail and a door glass arranged inside a vehicle in a width direction of the inner panel are eliminated for further securing the inner space.
For example, as a door inner panel in FIG. 1 replaces a function of a door outer rail, an existing door inner rail may be mounted to be closer to an inner side of the vehicle.
Moreover, as a trim seal for controlling the amount of water entering along a door glass surface is attached to an inner side of the vehicle in a width direction of the door inner rail, of which a position and a shape are changed, watertight performance may be improved since the trim seal may extend up to an upper side of the door trim as shown FIG. 1.
However, even if the door inner rail is eliminated according to the related art, assemblability and stiffness of the door inner belt need to be improved.
Further, buzz, squeak, and rattle (BSR) of the vehicle door, which causes due to the assembly structure of the door trim and the door inner rail, particularly, when a supporting structure of the door trim and the door inner belt in a width direction of the door is not adequately strong, also needs to be improved.
Moreover, if the door inner rail can be fabricated by roll molding rather than by press molding, stiffness of the structure may be improved and cost may be saved.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure, and therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.